Desert Rosemallow (Hibiscus coulteri)
This hibiscus flower is cup-shaped, with 5 rounded petals and a distinctively red basal spot. You can see two of the upper leaves at the left edge of the flower, dark green and toothed with 3 lobes.
The cup-shape is evident in the image at left. The image below shows an array of leaves at the top of the plant, but the lower leaves, which are not lobed but undivided, are not visible here. (Click on the image below to enlarge it.)